Vehicle-spring



UNITED STATES ENCE'.

PATENT l EDWARD SPAULDING, OF BROOKLYN, NEW YORK.

VEHICLE-SPRING.

dated August 2, 1881.

Application filed May 3l, 188i. (No model.)

To all whom it may concer/n:

Be it known that I, EDWARD SPAULDING, of Brooklyn, Kings county, andState of New York, have invented a new and useful Improvement inVehicle-Springs, of which the following is a specification. y

The invention relates to elliptic or semielliptic springs the plates ofwhich are of concavo-convex form in cross-section, and are so arrangedin the spring that the edges of the plates are subject to compressiononly in service, while the tension is borne by the intervening webbetween the edges in a manner calculated to add greatly to thesustaining capacity of the metal as compared with the arrangement ofsuch concave-convex plates that the edges are exposed to the tension,because the compression of the edges tends to prevent the opening of theslight cracks or fissures of the edges of the metal where, it is weakestand the breaks begin, whereas the tension acts the reverse on saidedges.

The iirst part oftheinvention consists of makin g these plates ofgreater thickness in the middle portion, which sustains the tension,than the edges, which are subject to the compression, and also makingboth sides of these concavoconvex plates upon the same radius orcurvature in cross-section, whereby two important advantages areobtained over all springs of this character heretofore made, viz: First,the metal is thus disposed more naturally in accordance with the demandsof the service by giving the larger portion, and also that por` tionwhich is best adapted to resist tension, to the locality where thetension is sustained and the lesser to the parts of compression, andthus for given quantities of metal greater power is secured; second, theplates bear alike upon 'each other throughout their whole area, and

thereby are less injured by friction and their sustaining power isincreased.

The second part of the invention consists of making the studs of theseconcavo convex plates that are struck up on one side by indenting theother side for keeping the plates in position to project from the convexside of said plates, whereby they are more in conformity with the shapeof the plates than they would be on the other side, and the continuityof the surface is less disturbed and broken, and convexity of surfacecorresponding to the general convexity of the plate is presented to thetension, whereasV if struck up on the other side the convex surface ofthe plate would be broken by the indentations, which would weaken theplate to a great extent by making abrupt angles, favorable to cracks.

The third part of the invention consists of making the band which isemployed to hold the several plates of the spring together and to form abearing-surface between the spring and the part of the carriage to whichit is attached with a flat outside surface for saidA bearing and aconvex inner side corresponding with and fitting in the concave outersurface of the outer concave plate, and thereby making said outsidebearing adapted to the carrage, and the inside bearing adapted to thespring and supporting it across the whole breadth; but I do not limitmyself to this construction of the band, for I may use a separate piecefitted in the space between the concave side of the spring and the band,if the latter is straight on the inside.

Figure 1 in the accompanyings is a perspec-` tive view of an ellipticspring made of concavoconvex plates arranged for the convex sides tosustain the tension while the edges take the compression. Fig. 2 is alongitudinal section of a half-spring of similar arrangement, and itshows my arrangement of the studs and cavities for confining the plates.Fig. 3 is a transverse section of Fig. 1, showing both sides of theplates constructed on the same curvature and made thicker in the middleand thinner at the edges, in accordance with the present invention. Italso shows my arrangement of the studs and cavities for confining theplates with relation to said concavo-convex plates. Fig. 4 shows aslight modification of the form of these studs and cavities.

By reference to Figs. 1 and 2 it will be readily observed that theeffect of a load upon springs constructed of concavo-convex plates asthere represented, and arranged with the convexrsides toward the chordof the arc formed by the longitudinal direction of the spring, is toproduce tension on the middle web and compression on the edges. N ow, itis evident that the effect of compression is much less destructive tothe integrity of the metal than that of tension g hence if the metal isso disposed in the construction ofthe plates as to make them thinnest atthe edges and thickest at the middle, it is best arranged to suit therequirements of the plates of this form and arrangement, and thus Willbe best adapted to secure 'the best results with the least amount ofmetal, a

matter of great importance in the Way of economy of metal, also labor inthe construction of the springs, for the smaller the quantity of metalthe less the amount of labor and power required to shape them, and forvehicle-springs lightness is also of great importance. Again, it will beobserved that by this same construction of these concavo-convex plates,thicker at the middle and thinner at the edges, they are made to bearthe one upon the other with uniformity throughout their WholeA surface,so that the friction and Wear are no greater on one part than anotherand each plate is sustained by the other, and the effect of the load isevenly distributed over the whole spring so as to have the best effects,whereas if the plates have parallel sides, or are thicker at the edgesthan the middle web, they can only bear along the edges, Where theywill, as a matter of course, Wear faster and unequally, and they will beless powerful, both singly and together. For this part-that is, to causethe plates to bear fairly upon each other-both sides should be formed onthe same radius or curvatures, as indicated by the dotted lines a, Fig.3, which are prolonged beyond the edges of the plates b, to show moreclearly the taper of the plates from the middle to the edges; but forthe advantage of the thicker middle and thinner edges, merely in pointof the best distribution of the metal-for instance, in a spring-havingonly one plate-I do not confine myself to the same radius for both sidesof the plate, for the concave side may be of a greater radius, makingthe edges still thinner in proportion to the middle, if desired.

c represen tsthe studs, thrust out on one side by indentations d made onthe other, to secure the plates in position Within the band e, by thestud of one plate iitting in the indentation of another, as is common insprings; but in this case these studs, being formed on theseconcave-convex plates, are, according to my invention, arranged toproject from the convex sides for maintaining the continuity of theconvex surface, as before described, and thereby. preserving theadvantage gained by presenting the convexity of the spring to thetension of service.

The curvature Which I prefer for the crosssection ot' the plates is thatof which the chord of the concave side of the plate equals the 'radiusof the circle, but it may be varied at Will and the plates may haveparallel edges from middle section to end` or be tapered, and thecurvature may vary from middle to end, if desired.

That side of the band c which crosses the outer concave side of thespring is required to be flat on its outside, 7L, for properlyconnecting With the carriage. At the same time, the

concavity of the plate must be filled inside of the band, to affordsubstantial rest and holding for the plate. Therefore, in order toaccomplish this Without the use of an additional piece to be shaped andiitted in for that purpose, I propose to make the band withone of itssides flat outside, at h, and convex inside, at i, in conformity Withthe concavity.

It is designed to fit on the band e while hot and enlarged enough toadmit the stud c of the bottom plate to its cavity f in the band, andafter the band has shrunk tight fit in the binding-screw g.

I olaim- I. 1. In elliptic or half-elliptic springs made of one or moreplates of concavo-convex form in cross-section, and so arranged that theload causes compression on the edges and tension on the middle web ofsaid plate or plates, the said plate or plates made thickest in themiddle and thinner at and toward the edges, substantially as described.

2. In elliptic or half-elliptic springs made of one or more plates ofconcavo-convex form in cross-section, and so arranged that the loadcauses compression on the edges and tension on the middle Webs of saidplates, the said plates having both their concave and convex sidesconstructed on one and the same curvature or radius, and thereby madethicker in the middle than at the edges, and also made to bear uniformlyand alike upon each other from edge to edge, substantially as described.

3. In elliptic or half-elliptic springs made of a concavoconvex plate orplates in cross-section, and arranged so that the load causes thecompression on the edges and tension on the middle web of said plate orplates, the stud or studs for securing the plate or plates in positionstruck up on the convex side thereof by indentation of the concave side,substantially as described.

4. The combination, with a spring, the plate or plates of which are ofconcavo-convex form in cross-section, of a band, e, that is convex onthat portion of the inner side that crosses the concaveside of thespring, and ittin g the concavity thereof, and is shaped on the outsideof said portion in tlat or other equivalent' form, adapted for thebearing-connection With the carriage, substantially as described.

EDWD. SPAULDING.

Witnesses W. J. MORGAN, S. H. MORGAN.

IDO

IOS

'in -i eers Patent No. 245,097.

Correction n; is hereby certified that in Letters Patent No. 245,097,issued August 2,1s81,t0 Edwqrd Spaulding for an improvement in lspecification attched to and forming a part of the said Letters Patent,in line 76, the word accompanying7 was erroneously printedaccompanyings5 'falso that the Word was erroneously omitted after saidWord accompanying that thel proper have been Ina'de in the les andrecords pertaining tothe drawing corrections case in the Patent Office,and are hereby rnade in said Letters Patent Signed, oountersigned, andsealed this* 27th day of September, A. D. 1881.

[ISEAL] A. BELL,

Acting Secretary of the Interior.

E. M. MARBLE, Y

Commissioner of' Patents.

Vehicle Springs, on page 1 of the printed t

